Sequential pulsation timer



July 8, 1958 J. L. SOLOMON SEQUENTIAL PULSATION TIMER 5 Sheets-Sheet 1Filed June 15, 1953 INVENTOR Lia/4w Z. Jalorrzoiz, BY

J. L. SOLOMON 2,842,315

SEQUENTIAL PULSATION TIMER 5 Sheets-Sheet 2 July 8, 1958 Filed June 15,1953 July 8, 1958 J. L. SOLOMON SEQUENTIAL PULSATION TIMER 5Sheets-Sheet 4 Filed June 15, 1953 H W i QWWW j H w R m m M gc im i H MH M M w H. H H H M N \mw Q 1 I w I A TQM \fi wfi QQN MNN RN 3 VIII lllwlwumw mllllL gm swm i w% United States Patent SEQUENTIAL PULSAT IONTIMER Julius L. Solomon, Chicago, Ill., assignor to Welding Research,Inc., Chicago, Ill., a corporation of Illinois Application June 15,1953, Serial No. 361,668 11 Claims. (Cl. 235 132) The invention relatesto an electronic timing system for the individual timing of a number ofoperations or functions taking place in sequence such as may beperformed by a welding machine and has reference more particularly to atiming circuit employing electronic elements including a cold cathodeglow transfer tube in combination with control means therefor foreffecting a counting function.

Objects of the invention are to provide an improved electronic systemwhich will accurately time any desired operation by counting apredetermined number of electric pulses supplied by an electric currentsource; to provide an electronic timing system as described which may beutilized as a pulsation timer or as a heat-cool timer for seam welding;and to provide an electronic timer which will be simple in construction,embodying relatively few parts, and wherein the parts can be duplicatedand connected in series relation for adding additional stages to thesystem.

A further object resides in the provision of a pulsation timer whichwill utilize two or more cold cathode glow transfer tubes as thecounting elements, and wherein circuit control means are provided forswitching from one counting element to the next at the end of theircounting function.

A more specific object is to provide a pulsation timer which willincorporate a pair of counting elements as herein described incombination with a control circuit for switching the counting functionfrom one element to the other so that they alternate in operation.

Another object resides in the provision of counting elements for atiming circuit and wherein said elements are electrically connected by acontrol circuit and by a commutating circuit, the latter circuitincorporating electric translating means for transmitting pulses andwhich are so connected to the elements that certain translating meanswill supply current pulses to be counted to one element and will supplycurrent pulses for resetting purposes to another of the elements.

With these and various other objects in view, the invention may consistof certain novel features of construction and operation as will be morefully described and particularly pointed out in the specification,drawings and claims appended hereto.

in the drawings which illustrate an embodiment of the device and whereinlike reference characters are used to designate like parts:

Figure l is a view illustrating schematically the various elements andcircuit connections comprising the cold cathode glow transfer tubeemployed by the present invention as a counting instrumentality;

Figure 2 is a wiring diagram schematically illustrating the controlcircuit for switching the counting function from the countinginstrumentality of one stage to the counting instrumentality of the nextstage;

Figure 3 is a wiring diagram of the control circuit for a commercialform of pulsation timer coming within the invention;

Figure 3A is a view illustrating schematically the various elements andcircuit connections for a pair of counting instrumentalities such asemployed by the invention and which are electrically connected to thecontrol circuit of Figure 3; and

Figure 4 is a wiring diagram schematically illustrating a modified formof timing system coming within the invention and wherein a series ofcold cathode glow transfer tubes are employed for effecting functions insequence.

Figure l of the drawings illustrates in diagrammatic form a cold cathodeglow transfer tube which comprises the counting element for the presentcontrol circuit and to which is connected a source of direct currentwhereby the tube is energized. Other terminals of the tube connect witha sinusoidal pulse source, the pulses of which are counted by the tubeduring a counting function, and still other terminals of the tube areconnected electrically to means whereby the tube can be reset each timefor a predetermined count following an operation thereof. Said tube It)is characterized by a single anode l1 and a plurality of cathodes 12,13, 14, etc., ending with the last cathode 16. In a ten-cathode tubecathode 16 would therefore be the last or the tenth cathode, whereas, ina twelve-cathode tube said cathode 16 would be the last or twelfthcathode. It will be observed that the terminal C is electricallyconnected to cathode 16. In the construction of the tube the cathodesare arranged in a circle so that all will be relatively adjacent thecommon anode l1, and in order to transfer the glow from one cathode tothe next in succession, the tube is provided with guides 18 and 20, thesame being associated with each cathode. The conductors 21 and 22connect the guides respectively to the guide terminals 23 and 24.Accordingly, a current pulse applied to terminal 23 will be supplied inturn to all of the guides 18 and in a similar manner a current pulseapplied to terminal 24 will be supplied to all of the guides 20.

The anode 11 is connected through resistance 25 and by a conductor 26 tothe positive terminal 27 of a source of direct current, the voltage ofwhich may be in the neighborhood of four hundred volts. The negativeterminal of said direct current source has connection with conductor 28leading to terminal D. The function of terminals C and D will beunderstood as the description proceeds. Each cathode is electricallyconnected to conductor 28 by a resistance circuit which includes aswitch, as clearly shown in Figure 1. For example, cathode 12 isconnected by the resistance 3t) and switch lever 31 to conductor 28, andin a similar manner cathode 13 is connected by resistance 32 and switchlever 33 to said conductor. With respect to the remaining cathodes, acircuit, including resistance and a switch lever, is provided, with theexception of cathode 16, which is connected to conductor 28 by circuit33, which includes resistance 39 only. The conductor 40, havingconnection with terminal G, is associated with conductor 28 and isconnected by conductors 41, 42, 43 and 44 to switch terminals 45, 46, 47and 48, respectively. It will be observed that the switch terminals 31,33, 35 and 37, etc., have selective positions, in one of which theyelectrically connect with conductor 28 and in the other, theyelectrically connect with terminals 45, 46, etc., and with saidconductor 40 leading to terminal G. The position of the switch elementsfor the various cathodes, whether connected to conductor 28 or conductor40, will determine the particular cathode selected for starting acounting function. In the diagrammatic illustration of Figure 1 thesecond cathode, namely, 13, has its switch element 33 connected toterminal 46 so that this cathode has been selected for starting thecounting function and accord t.) ingly in a ten-cathode tube the elementwill count eight current pulses for each operation thereof.

The terminal A is connected by means of conductors 50 and 52 to guideterminals 25 and 24, the connection including condensers 51 and 53. Bothconductors and 52 are connected to a parallel circuit which includesrcsistances 54 and 5S. Said parallel circuit at a midpoint between theresistances is connected by conductor 56 to a potentiometer includingthe divider 5'7 and resistance 58, the latter being connected across thedirect current source previously described. It will be noted that pointer 57 is positioned at point 0 on the resistance 58 and thus the guides13 and it? are normally maintained at a slightly higher potential thanthat applied to the cathodesv The resistance 53 is connected at 61) toconductor the terminal B also has connection with said conductor 28through the conductor 61.

In the event terminals A and B are connected to a source of alternatingcurrent of sinusoidal wave form it will be understood that condenserstion with the connecting circuit, including the resistances 54 and 55,function as a phase shift circuit to shift the phase of the voltagesapplied to the guide terminals 23 and 24, For example, it is possible toapply to guide terminal 23 a leading voltage and to a guide terminal 24a lagging voltage so that the current impulse is first indi cated atguides 18 by a drop in the potential of said guides and after a timeinterval, depending on the characteristics of the phase shift circuit,the current pulse is indicated at guides 21. by a'sirnilar drop inpotential.

Thecounting element of Figure 1 is activated by the application ofperiodic impulses to terminals D and Since switch element 33 of cathode13 is theonly element connecting with terminal G the said periodiccurrent impulses produce a glow, between anode 11 and cathode 13. Toinitiate a counting function current pulses are applied to terminals Aand B, the same having a uniform time interval such as may be producedby an alternating current of sinusoidal wave form. The application ofthe first pulse to terminals A and B will energize the guides 18 and theglow is accordingly transferred from cathode 13 to the guide 18associated therewith. Immediately thereafter the guide 2%, associatedwith cathode 13 is energized and the glow is transferred from guide 13to guide 20. Upon decay of the voltage applied to guide the glow istransferred to cathode 14, since as explained, the guides are normallymaintained at a potential slightly above that of the cathodes. The nextimpulse applied to points A and B will cause transfer of the glow fromcathode 1 1 to guide 18 associated therewith, then to its guide 213, andthen to 15 the next cathode in succession.

Accordingly, for each impulse the glow is transferred from one cathodeto the next and a counting function accordingly takes place. At thecount of the eighth impulse the glow will have been transferred tocathode 16 representing the last cathode of the counting element.Immediately upon cathode 16 conducting the glow, current flow takesplace through resistance 39 of conductor 38 and the drop in voltageacross this resistance is exhibited at the terminals C and DJ Inaccordance with the invention the voltage thus appearing acrossterminals C and D is used to transfer the counting operation to a secondcounting element which may represent the second stage in a sequencingseries.

Figure 2 of the drawings is a wiring diagram illustrating in schematicforma control circuit for a two-stage counting system wherein each stageemploys a counting element such as shown in Figure 1, having terminals Aand B, C and D, and D and G. The main function of the control circuit isto alternately render conductive a pair of electric discharge valvessuch as thyratrons whereby the counting function is shifted from onecounting element to the next and so on, with the operation beingrepeated as long as the control circuit remains energized.

More specifically, the control circuit of Figure 2 is dis- 1 and 53 incombinaclosed in connection with two countingelements which aregenerally designated by numerals 7t) and 81 each element beingconstructed as explained in connection with Figure l and havingoperation to perform a counting of a predetermined number of electricalimpulses such as may be applied to the terminals A and B of theelements. The tliyratrons of Figure 2 are indicated by numerals '71 and31 and an electric discharge valve of the double triode type isindicated by numerals 72 and 82. The resistances 73 and 33 haveelectrical connection with the anodes of valves 71 and 31. The anodes ofthe double triode valve 72, 82 are respectively connected to primarywindings '74 and 84 of the transformers 75 and 85, each transformerhaving a pair of secondary windings 7c and 77 for transformer 75 and 86and 37 for transformer 85.

The control circuit is energized by a source of direct current connectedacross conductors 911 and 91 with the positive terminal of the sourceconnecting with conductor 9%. The resistance 92 connects at itsrespective ends with conductors 911 and 91 and is accordingly inparallel relation with the direct current source, the said resistanceand the pointer 93 providing a potentiometer which may be adjusted tovary the potential applied to the pair of thyratrons 71 and 81. Theconductor 94 connects with the pointer 13 and the resistances 73 and 83in turn have'con nection with said conductor 94 and with the anode 95 ofvalve '71 and anode 96 of valve $1. The cathodes '97 and 98 of saidvalves are joined by conductor )9 which is in turn connected toconductor 91 through resistance 1% and the condenser 101 in parallelcircuit relation with the resistance. The control grid 75 of valve '71is connected by conductor 162 to the terminal C of the counting element713, whereas the control grid 38 of valve 51 is connected by conductor163 to terminal C of the counting element Conductor $9, havingconnection with the positive terminal of the direct current source,leads to the cathodes 1M and 105 of the valve 7.2, 82. The anodes 1115and 1&7 thereof connect with the primary win-dings 74 and The controlgrid 103 of triode 72 is connected by conductor 10) to resistance 33,who ear; control grid 111 of triode 32 is connected by conductor 111 toresistance 73. Accordin ly, the conductivity of triode 72 is controlledby that of thyratron 71, whereas the conductivity of triod-e 82 iscontrolled by that of thyratron 31. p The primary windings 74- and 84 ofthe transformers 75 and 35 connect with one terminal of secondarywinding 112 of transformer 113. Said transformer 113 is provided withprimary winding 114, the terminals of which are suitably connected to asource of sixty cycle alternating current of approximately one hundredand ten volts. The opposite terminal of secondary Winding 112 isconnected by conductor 115 to the cathodes 104 and 1135 of the triodes'72 and 82. As previously explained, the primary windings 74 and 84 eachhave associated therewith a pair of secondary windings, as clearly shownin Figure 2. Secondary winding 76 is connected by conductors 116 and 117to terminals D, G, respectively of the counting element 71?. in asimilar manner secondary winding 86 is connected by conductors 118 and119 to the terminals D, G, respectively of counting element St).Secondary winding '77 is connected through conductors 120 and 121 toterminals A, B of the counting element 80. Secondary winding 37 isconnected by the conductors 122 and 123 to the terminals A, B of thecounting element 70. Conductor 124 connects conductor 91 with terminal Dof counting element 79, whereas conductor 125 in a similar mannerconnects conductor 91 to terminal D of counting element St). A bypasscircuit is provided in connection with conductors 116 and 117, the sameincluding the direct current battery 126 and switch 127. Conductor 117and thus terminal G of counting element 70 can be connected to thepositive end of the battery 126 through switch 127. The negative end ofthe battery has connection with conductor 116. Conductor 122, leading toterminal A of the counting element 70, is provided with a main switch128 which controls the operation of the control circuit and the startingof the counting functions of the elements 70 and 80. It will be observedthat the main switch 128 has a fixed relation through member 130 withswitch 127 so that when one switch is closed the other is positivelyheld open.

For explaining the operation of the control circuit of Figure 2 it willbe assumed that switch 128 is closed and that thyratron 71 isconducting. Accordingly, a voltage will exist across resistance 100 inthe cathode circuit common to both thyratrons so that a negative bias ismaintained on the screen grid of thyratron 81. If a positive pulse issupplied by terminals C, D of counting element 80 the thyratron 81 willbecome conductive and 71 will be rendered nonconductive. This switchingfrom one tube to the other is effected by the capacitor 131. While tube71 was conducting capacitor 131 was charged in a manner whereby the endof the capacitor which is connected to the anode of tube 71 is negativeand that end which is connected to the anode of 81 is positive. When 81is rendered conductive by the positive pulse applied to grid 33, thepositive end of capacitor 131 is electrically connected with the cathodeof 71 so that the anode 95 of said tube is thus made negative withrespect to its cathode which extinguishes said tube.

With thyratron 31 conducting, it will be seen that a voltage drop willappear across resistance 83 between the slider in contact therewith andthe positive end of said resistance. This voltage is applied to the grid108 of the triode 72. In the some grid circuit there is also a voltageappearing across the resistance 92 from the positive end to the slider93. Between grid 19% and cathode of the triode 72 there is thus the sumof said two voltages, one appearing across part of resistance 92 and theother across part of resistance 83. The voltage across part of 92 issufficiently low to allow the triodes to conduct. However, the additionof the voltage across part of resistance 83 brings the grid 108 to thecutoff region and stops conduction of 72. Accordingly, with thyratronill conducting, triode 7.2 will be held nonconductive, whereas, triode82 will be conducting since there is no voltage appearing across theresistance Transformer 35" will therefore be passing current and analternating voltage will be induced in its seconda y winding: 3'5 87.The current pulses generated in the secondary winding 86 are applied toterminals D, G of the counting element 80 and a periodic glow is thusmaintained in said counting element from anode to the patricular cathodewhich has been selected for starting the counting function, alldepending on the particular count desired of this element. The currentpulses generated in secondary winding 87 will be applied to terminals Aand B of counting element 70 and said element is thus operative toeffect a counting function. The number pulses to be counted by element7i) will, of course, depend on the cathode selected for starting thecount. When the glow has been transferred to the last cathode of thecounting element 70 the voltage caused to appear across terminals C, Dthereof will apply a positive pulse to thyratron 7 i, causing it tobecome conductive. The same action involving the capacitor 131 takesplace as before and thyratron 81 is immediately extinguished. t ith tube71 conducting, a voltage drop now appears across '73 and there is novoltage across 83. This switch in the conductivity of the thyratronseffects a switch in the conductivity of the triodes so that 32 isextinguished and triode 72 is rendered conductive. Transformer '75accordingly pass-cs current and pulses are induced in its secondarywindings. The current pulses induced in winding 76 are applied toterminals D, G of counting element 70 to reset this element in a manneras previously explained. The current pulses induced in winding 77 areapplied to terminals A and B of counting element 80 and this element nowbecomes operative to effect a counting function wherein each pulseapplied to terminals A and B will be counted by a transfer of the glowfrom the starting cathode to the last cathode, whereupon a signalvoltage is produced across its terminals C, D. As previously explained,this signal voltage applies a positive pulse to the grid 88 andthyratron 81 is again rendered conductive, thus completing the cycle ofoperations.

The counting functions will alternate between elements 70 and and aslong as the initiating switch 128 is maintained in closed position. Ifthe switch is thrown to off position while counter St) is in operationthe counting by this element will continue to the end of the count,after which the control circuit will become inoperative. Thus the heattime is never cut short. However, should switch 128 be opened during theoperation of counting element 79 for the cool time, the countingfunction will stop immediately since the pulses to terminals A and B arediscontinued. With the opening of 128 switch 127 is automatically closedand counting element 70 is accordingly reset by the current supplied bybattery 116.

The timing system of Figure 2 will operate in a manner to give accuratetiming functions and such a system will find extensive utility as apulsation timer or as a heatcool timer for seam Welding. The countingelement 80 would function to time the duration of the welding heat andtiming element 70 would operate to time the duration of the coolingperiods between welds. For a sequenc' ing timer for timing three or moreoperations taking place in sequence the system could be amplified byadding additional stages, each stage incorporating a counting elementhaving the characteristics and mode of operation as described.

Referring again to Figure 1, a modification is disclosed for resettingthe counting element at the end of. each counting function. Theterminals E, F are substituted for terminals D, G. Said terminals haveconnection respectively with conductors 132 and 133 which are connectedby the current limiting resistor 13 3. Conductor 132 leads to the grid135 of the electric discharge tube 136. The anode 137 of said tube isconnected to conductor 40 and through current limiting resistor 138connection is made with conductor 28. The cathode 140 is joined byconductor 41 to the positive end 142 of the battery 143, the negativeend of which connects with conductor 133. A second battery is employed,namely, 144, the same being joined by conductor 145 to terminal 142 andby conductor 146 to conductor 28.

When the resetting pulses are applied to terminals E and F in the manneras described with respect to terminals D, G, it will be understood thattube 138 will be rendered conductive and will thus transmit amplifiedcurrent pulses to maintain the glow between the anode 11 and theparticular cathode selected for initiating the counting function. Whenthe pulses to terminals E and F are terminated the tube 138 is held in anonconductive state since grid 135 is maintained at a potential which ismore negative than its cathode 140.

Figures 3 and 3A are wiring diagrams schematically disclosing acommercial form of counting system wherein a pair of the countingelements of Figure 1 are al ternately controlled as regards theircounting function by means of a control circuit. Figure 3 is analogousin all respects to the control circuit shown in Figure 2 and similarelements are identified by related reference numerals. The thyratronsare numbered 271 and 281 and the resistors connecting with therespective anodes of the thyratrons are identified by 273 and 283. Thus,as previously explained, the conductivity of the thyratrons controls theconductivity of the triodes 272 and 282. The transformer 275 isassociated with triode 272 and transformer 285 is associated with triode282. Each transformer has a pair of secondary windings which are '2connected by suitable conductors to certain terminals of the countingelements 270 and 28?; shown in Figure 3A.

As a result of the showing made by Figures 3 and 3A it is possible toobtain an understanding of the manner in which the electronic partswithin the counting elements 270 and 28! are electrically connected tothe secondary windings of the transformers which comprise the impulsegenerating devices of the control circuit. Considering first winding277, it will be observed that the same is connected by conductors 32%and 321 to terminals A and B of the counting element 280. In a similarmanner winding 287 is connected by conductors 322 and 323 to terminals Aand B of the counting element 270. Also by tracing the circuits for thewindings 276 and 286 it will be seen that these are electricallyconnected to terminals D and G, there being provided in thismodification a double diode 32.9 interposed in the circuits for thewindings respectively. Also the switch 328 has a fixed relation withswitch 327 through member 330 so that when one is open the other isclosed. With the opening of switch 328, if counting element 289 is inoperation, it will continue until the end of the counting function andthus the heat time is never cut short. However. it counting element 270for the cool time is in operation when switch 32% is opened, itscounting function is ended immediately. Switch 327 is simultaneouslyclosed and the current source 316 is rendered operative for resettingthe counting element.

Referring to the modification shown in Figure 4, it will be observedthat four counting elements are employed. the same being identified bynumerals 410, 411, 412 and 413, and accordingly this modification of theinvention provides a sequence timer wherein each event in the series isindividually timed by its respective counting element. Each elementconsists of a cold cathode glow transfer tube embodying the same circuitelements and circuit connections as i lustrated in connection with thetube of Figure 1. Each counting element is therefore provided withterminals A, B; C, D; and D. G. The said terminals A, B are connectedwith suitable means for supplying current pulses to the elements to becounted thereby. A signal voltage is produced across terminal C, D tosignify the end of the counting operation of its respective element andthe terminals D, G connect with the resetting means of each countingelement so that the element can be reset by a resetting pulse appliedacross said terminals.

The counting elements are electrically connected by an improved controlcircuit essentially consisting of the cold cathode gas tubes 414, 415.416 and 417 and the cathode resistors 41%, 419, 420 and 421,respectively. Each of the cold cathode gas tubes consists of an anode. acathode, and a control grid. With respect to tube 414-. it will be seenthat the anode 422 is connected to the conductor 423, comprising thepositive terminal of the direct currentsource, which is provided forenergizing the said gas tubes. The conductor 424 constitutes thenegative terminal of said power source, and the cathode 425 of the tube4-14 has electrical connection through the cathode resistor 418 withsaid negative conductor 424. said conductor being additionallyconnectedthrough 42a to terminal D of the counter 410. Terminal C of said counteris connected through conductor 427, condenser 428, and switch 439 withthe grid 431 of tube 414.

The counting element 4-11 is similarly connected through its terminalsC, D to cold cathode gas tube 415, the anode 432 thereof havingconnection to the positive conductor 423, the cathode 433 thereofconnecting through resistor 419 with negative conductor 424 and the grid434 having connection through conductor 435 to terminal C. The terminalD is connected through conductor 436 to 424. Similar elementselectrically connect the terminals C and D of counting element 412 withtube 416 and likewise counting element 413 is connected with tube 417.With respect to this last tube,

C} attention is directed to switch 447 which is interposed in thepositive conductor 423 at a point beyond the connection theretoof theanode 442 of said tube. Accordingly, it will be seen that the anode isat all times con nected to said positive terminal so as to energize tube417.

The invention provides means for switching the conductivity from onecold cathode tube to the next. For example, should tube 414 beconducting and should tube 415 be rendered conductive, then tube 414 isimmediately snuffed out by the capacitance having electrical connectionwith the cathode circuits of the tubes. The conductor 4-48 electricallyconnects the four cathodes of the tubes respectively and in between eachtube there is interposed a condenser 450, the operation of which is suchthat only one tube may be conductive at a time. Such operation will bepresently described in detail.

The transformers 451, 452, 453 and 454, in combination with the vacuumtubes 455 to respcstively, constitute a pulse-sending or commutatingnetwork for the purpose of transmitting current pulses to be counted bythe counting elements and for additionally transmitting reset pulses tosaid elements. The vacuum tubes are connected in parallel acrossconductors 46% and 461, the said conductors constituting the terminalsof the secondary winding 462 of the power transformer 453 having primarywinding 464. The terminals of winding and are connected to any suitablesource of alternating current identified by leads L and L With respectto vacuum tube 455, it will be seen that its anode 465 thereof isconnected to primary winding 45:; of transformer 451, which windingis inturn connected to conductor 469. The cathode 467 of said tube 455 isconnected to conductor 451, whereas the grid 1 tliereo. has electricalconnection through conductor 57% to cathode 443 of the gas tube 417,said connection being made between the cathode and resistor 421 and saidtube. in a similar manner the vacuum tube 256 is connected across theconductors 460 and 461, with the grid being electrically connected byconductor 4-75 to the cathode 425 of tube 414 at a point between thetube and the cathode resistor 418. Similar connections are provided forvacuum tubes 457 and 453, it being seen that the grid 479 of tube 457 isconnected by conductor 48-3 to cathode 433 of the gas tube 415, whereasvacuum tube 453 has its grid 484 connected through conductor to cathode438 of the gas tube 416. A source of biasing potential in the form of adirect current battery 43% has its positive terminal connected toconductor 461 with its negative terminal being electrically connectedthrough conductor 487 to the negative conductor 424.

Referring more particularly to transformer 455., it will be understoodthat this transformer is provided with a plurality of secondarywindings. One winding 4-238 is connected through conductors 4% withterminal A, B of element 410. The other secondary windings thereof haveconnection with the reset terminais D, G of counting element 411, 412and 413, respectivel Transformer 452 has two secondary windings, windingidentified by numeral 491 having electrical connection with the resetterminals of counting element 43th, with the other secondary winding,namely, 492;, of said transformer having electrical connection withterminals A, B of counting element 411. Transformer is provided with onesecondary winding, namely, 4-5 3, which has electrical connection withterminals A, B of counting element 412 and in a similar mannertransformer 454 has one secondary winding, namely, 494, whichelectrically connects with terminals A, B of counting element 413.

With switch 447 in the position as shown, the gas tube 417 is renderedconductive and the same will pass current from the positive terminal tothe negative terminal of the direct current power source. Current flowas permitted by the conductivity of this gas tube will produce a voltageacross the cathode resistor 421. From an examination of the cathode togrid circuit of vacuum tube 455, it will be seen that battery 486supplies a negative bias to the grid 4T8 thereof through resistor 421and conductor 47%. This same bias is supplied to the grid of vacuum tube456', 457 and 458 through the cathode resistors 418, 419 and 420, andrespective grid conductors. These tubes are therefore normallymaintained in a nonconductive state by this negative biasing Voltage.With the gas tube 417 conducting, the voltage across resistor 421 issuflicient to bring the grid of vacuum tube 455 to a positive potentialwith respect to its cathode and the vacuum tube accordingly conducts topass alternating current pulses from the power supply L L through theprimary winding 466 of transformer 451. One secondary Winding, namely,483, of this transformer is connected to terminals A, B of counter 41%and said counter accordingly begins a counting operation to count thepulses thus supplied thereto by transferring the glow from cathode tocathode of said counter, all as explained in connection with Figure 1.When the glow has been transferred to the last or tenth cathode avoltage pulse is applied to terminals C, D of said counting element 410and the counting operation is repeated. However, inasmuch as switch 43bis open the voltage pulse is not supplied to gas tube 414. Theadditional secondary windings 4% of transformer 451 have connection withthe reset terminals of counters 413, respectively, and the voltagepulses generated in these secondary windings serve to reset the threecounters to a preset position.

When switch 447 is moved into an upward position to connect conductor423 to the positive terminal of the direct current supply source andwith switch 430 being closed, it will be seen that the voltage pulseapplied across terminals C, D of counting element 410 will eventually besupplied to grid 431 of gas tube 414, rendering this gas tubeconductive. By reason of the capacitance 450 having electricalconnection with the cathodes of the gas tubes, the tube 417 isextinguished. This is due to the fact that with both tubes, namely, 417and 414, conducting, the action of the capacitance is to render thecathode of tube 417 positive with respect to its anode, which results instopping the conduction of this gas tube. The grid 468 of vacuum tube455 will return to its negative biasing potential to stop conduction ofsaid tube and simultaneously tube 456 will conduct inasmuch as the gridthereof is brought to a conducting potential by the voltage drop acrosscathode resistor 418. Counting element 411 is now rendered operativesince current pulses to be counted are supplied thereto throughsecondary winding 492 of transformer 452. As the glow is transferredfrom the cathodes of counting element 411 from its preset position toits last or tenth cathode, a pulse will eventually be generated, whichis supplied through conductor 435 to the grid of gas tube 415. Thisvoltage pulse starts conduction of tube 415 and simultaneouslyextinguishes conduction of tube 414. With tube 415 now conductive thegrid 475 of vacuum tube 457 is brought to a conductive potential so thatthis vacuum tube fires and current pulses to be counted are now suppliedto counting element 412 through secondary winding 493 of transformer453. Eventually this counting element will reach the end of its countingoperation to supply a voltage pulse to the grid of gas tube 416.Conductivity of this gas tube will cause vacuum tube 458 to conduct andas a result current pulses to be counted are supplied to countingelement 413 through secondary winding 494 of transformer 454. When theglow is transferred to the tenth cathode of element 413 the end of itscounting function is indicated by the single voltage supplied to thegrid of gas tube 417 and once again this tube is rendered conductive toetfect conduction of vacuum tube 455. The counting procedure abovedescribed will continue from one counting element to the next insequence as long as switch 430 remains closed. Should this switch 430 beopened dur- 411, 412 and ing any pant of the operation, the countingsequence will continue until vacuum tube 455 is again renderedconductive. With switch 430 being open the control circuit is renderedinoperative so that the sequencing, as regards the counters, isterminated. However, the circuit remains ready for operation at alltimes and it is only necessary to close switch 43% to start the countingfunction with counting element 410 and continuing in sequence throughthe other counters.

The timing system of Figure 4 is characterized by a series of coldcathode glow transfer tubes which constitute counting elements and whichare electrically connected to a control circuit for switching from onecounting element to the next as each element completes its countingfunction. The circuit elements for the timing system are completed by apulse transmitting or commutating circuit which is electricallyassociated with the control circuit. In operation the counting elements411, 412 and 413 may control the squeeze time, the weld time, and thehold time, respectively, of a welding operation, for example, with thecounting element 410 controlling the off time. The timing system is soconstructed and arranged that an accurate count is secured for eachcounting operation of the elements 411, 412 and 413 and if the saidoperations are repeated the counting element 410 will produce a fullcount for the offtime period, all as determined by the presetting of theelements. Also, it will be understood that upon opening of switch 430the timing system will continue in operation until gas tube 417 isrendered conductive, which energizes vacuum tube 455, controlling theoflti-me counting element 410. For timing more than four operations, itis only necessary to add additional stages to the system as shown inFigure 4, with each stage incorporating a counting element, a gas tubeand a vacuum tube, all having the circuit connections and mode ofoperation as described.

The invention is not to be limited to or by details of construction ofthe particular embodiment thereof illustrated by the drawings, asvarious other forms of the device will of course be apparent to thoseskilled in the art without departing from the spirit of the invention orthe scope of the claims.

What is claimed is:

1. In a pulsation timer, the combination with a first counting element,a second counting element, and an electric source providing periodiccurrent pulses to be counted by the elements, of 'a control circuit forrendering the counting elements alternately operative for performing acounting function, said control circuit providing first and secondelectric translating means having connection with the electric sourcefor transmitting the periodic current pulses to the elements, the firsttranslating means transmitting to the second element current pulses tobe counted thereby and transmitting to the first element current pulsesfor resetting the element, the second translating means transmitting tothe first element current pulses to be counted thereby and transmittingto the second element current pulses for resetting the element, anelectric discharge device for each electric translating means forcontrolling by its conductivity the energization of its particulartranslating means, said discharge devices being electrically connectedin a manner whereby only one is conductive at a time, and meanselectrically connecting the counting elements with the discharge devicesin a selective manner, whereby each element at the completion of itscounting function supplies a signal voltage to a certain one of thedischarge devices to effect alterna-te conductivity of the dischargedevices.

2. In a pulsation timer, the combination with a first counting elementfor counting electric current pulses, a second counting elementidentical in construction and operation to the first, and an alternatingcurrent source providing periodic current pulses to be counted by saidelements, of a control circuit for rendering the counting elementsalternately operative for performing a counting function, said controlcircuit providing first and second transformers each including a pair ofsecondary windings inductively connecting with the electric source forsupplying the periodic current pulses to the elements, the firsttransformer supplying to the second element current pulses to be countedthereby and supplying to the first element current pulses for resettingthe element, the second transformer supplying to the first elementcurrent pulses to be counted thereby and supplying to the second elementcurrent pulses for resetting the element, an electric discharge devicefor each transformer for controlling by its conductivity current flowthrough its particular transformer, circuit means electricallyconnecting said discharge devices in a manner whereby only one isconductive at a time, and other circuit means electrically connectingthe counting elements with the discharge devices in a selective mannerwhereby each element at the completion of its counting function suppliesa signal voltage to a certain one of the discharge devices to effectalternate conductivity of the discharge devices.

3. In a pulsation timer, the combination with a first counting elementfor counting electric current pulses, a second counting elementidentical in construction and operation to the first, and an alternatingcurrent source providing periodic current pulses to be counted by saidelements, of a control circuit for rendering the counting elementsalternately operative for performing a counting function, said controlcircuit providing first and second transformers each including a pair ofsecondary windings inductively connecting with the electric source forsupplying the periodic current pulses to the elements, the firsttransformer supplying to the second element current pulses to be countedthereby and supplying to the first element current pulses for resettingthe element, the second trans former supplying to the first elementcurrent pulses to be counted thereby and supplying to the second elementcurrent pulses for resetting the element, an electric discharge devicefor each transformer for controlling by its con ductivity current flowthrough its particular transformer, each electric discharge deviceincluding an anode, a cathode, and a control grid, circuit meansconnecting said discharge devices in a manner whereby the conductivityof one is terminated upon the other being rendered conductive, and othercircuit means electrically connecting each counting element to thecontrol grid of a certain electric discharge device, whereby eachelement at the completion of its counting function supplies a signalvoltage to the grid of the discharge device connected thereto to effectalternate conductivity of the discharge devices.

4. Apparatus for counting electric current pulses by means of countingelements of the type employing an anode and a plurality of cathodes withguide terminals located between the cathodes, whereby the electricpulses energize the cathodes in succession and can therefore be counted,of a control circuit provided by said apparatus for controlling thecounting function of said elements, said control circuit including anelectric discharge device for each counting element to be controlled bysaid circuit, circuit means electrically connecting the dischargedevices in a manner whereby only one can be conductive at a time, atranslating device for each counting element, at least one of saidtranslating devices when energized transmitting to one counting elementcurrent pulses to be counted thereby and transmitting to another of saidcounting elements current pulses for resetting purposes, electricalconnections between the discharge devices and the translating devicesrespectively for individually energizing the translating eviccs as thedischarge devices are individually rendered conductive, and meanselectrically connecting the counting elements with the discharge devicesin a selsctive z .anncr, whereby-each element at the completion of itscounting functicn supplies a signal voltage to a certain one of thedischarge devices to effectconductivity thereof. 7 V

5. Apparatus for counting electric current pulses by means of countingelements of the type employing an anode and a plurality of cathodes withguide terminals located between the cathodes, whereby the electricpulses energize the cathodes in succession and can therefore be counted,of a control circuit provided by the apparatus for controlling thecountingfunction of said elements, said control circuit including anelectric discharge device for each element included in the controlcircuit, each discharge device having an anode, a cathode and a controlgrid, circuit means including capacitance electrically connecting thedischarge devices in a manner whereby upon any one device being renderedconductive the others are caused to become non-conductive, a transformerfor each counting element, each transformer supplying to one .iugclement current pulses to counted thereby and supplying to another ofsaid counting elements current pulses for resetting the element,electrical connections between the discharge devices and thetransformers respectively, whereby each discharge device by itsconductivity controls current flow through its particular transformer,and a conductor connecting each counting element with the grid of acertain discharge device, whereby each element at the completion of itscounting function supplies a signal voltage to one of the dischargedevices for effecting conductivity thereof.

6. For use as a pulsation timer, apparatus for counting electric currentpulses by means of electronic counting elements of the type employing ananode and a plurality of cathodes with guide terminals located betweenthe cathodes, whereby the electric pulses energize the cathodes insuccession and can therefore be counted, of a control circuit providedby the apparatus for controlling the counting function of the elements,said control circuit providing a plurality of translating means equal innumber to the counting elements and adapted to have connection with anelectric current source producing periodic current pulses, at least oneof said translating means supplying to the guide terminals of onecounting element current pulses to be counted thereby and supplying tothe resetting terminals of another of said elements current pulses forresetting purposes, an electric discharge device for each translatingmeans and having connection therewith for controlling by itsconductivity the energization of its particular translating means, eachdischarge device including an anode, a cathode and a control grid, andcircuit means electrically connecting each counting element with thecontrol grid of a certain discharge device, whereby each element at thecompletion of its counting function supplies a signal voltage to thegrid of the discharge device connected thereto to conductivity of saiddischarge device.

7. For use as a pulsation timer, apparatus for counting electric currentpulses as defined by claim 6, wherein each translating means includes atransformer having a primary winding connected to the electric currentsource and having two secondary windings, one secondary winding thereofsupplying to the guide terminals of said one counting element thecurrent pulses to be counted thereby and the other secondary windingsupplying to the said re setting terminals of another of said elementsthe current pulses for resetting purposes, wherein the circuit meanselectrically connects the last cathode of each counting element with thecontrol grid of a certain discharge device, and additionally includingresistance in the circuit of the last cathode of each element, wherebythe signal voltage produced by each counting element the end itscounting function is caused by the voltage drop acro s the saidresistance as a result of current flow taking place upon energization ofthe last cathode thereof.

8. For use as a pulsation timer, apparatus for counting electric currentpulses by means of electric counting ments of the type employing ananode and a plurality of cathodes with guideterminals located betweenthe cathodes, whereby the electric pulses energize the cathodes insuccession and can therefore be counted, said counting elements eachhaving input terminals, output terminals and resetting terminals, of acontrol circuit electrically connecting the elements in tandem relationand which controls the operation of the elements in sequence, saidcircuit including a source of electrical energy, an electric dischargevalve for each counting element connected across said source, circuitmeans connecting the output terminals of each counting element with thegrid and cathode of its respective discharge valve, whereby the signalvoltage produced by each element at the termination of a countingoperation thereof is caused to render its discharge valve conductive, acommutating circuit including an electric discharge valve for each valveof the control circuit, means in electrical connection with the firstvalve of the commutating circuit for supplying the input terminals ofthe first counting element with electric pulses to be counted therebyand for supplying to the reset terminals of the remaining countingelements electric pulses for resetting purposes, and other means inelectrical connection with each remaining valve of the commutatingcircuit for respectively supplying to the input terminals of theremaining counting elements electric pulses to be counted thereby.

9. For use as a pulsation timer, apparatus for counting electric currentpulses by means of electronic counting elements of the type employing ananode and a plurality of cathodes with guide terminals located betweenthe cathodes, whereby the electric pulses energize the cathodes insuccession and can therefore be counted, said counting elements eachhaving input terminals connecting with the guide terminals of theelement, output terminals across which there is produced a signalvoltage at the completion of the counting operation thereof, andresetting terminals to which there is supplied a current pulse forresetting purposes, of a control circuit electrically connecting theelements in tandem relation and which controls the operation of theelements in sequence, said circuit including a source of direct current,a normally non-conductive electrical discharge valve for each count ingelement connected across said source, circuit means connecting theoutput terminals of each counting element with the grid and cathode ofits respective discharge valve, whereby the signal voltage produced byeach counting element at the end of its counting operation will renderits discharge valve conductive, a commutating circuit including anormally non-conductive electric discharge valve for each valve of thecontrol circuit, a transformer having electrical connection with thefirst valve of the commutating circuit for supplying to the inputterminals of the first counting element electric pulses to be countedthereby and for supplying to the resetting terminals of the remainingcounting elements electric pulses for resetting purposes, and a secondtransformer for each remaining valve of the commutating circuit and inelectrical connection therewith for respectively supplying to the inputterminals of the remaining counting elements electric pulses to becounted thereby.

10. For use as a pulsation timer, apparatus for counting electriccurrent pulses by means of electronic counting elements of the typeemploying an anode and a plurality of cathodes with guide terminalslocated between the cathodes, whereby the electric pulses energize thecathodes in succession and can therefore be counted, said countingelements each having input terminals connecting with the guide terminalsand to which are supplied electric pulses to be counted, said countingelements each having output terminals across which there is produced asignal voltage at the completion of the counting operation thereof, andsaid elements each having resetting terminals to which there is supplieda current pulse for resetting purposes, of a control circuitelectrically connecting the elements in tandem relation and whichcontrols the operation of the elements in sequence, said circuitincluding a source of electric energy, a normally non-conductiveelectric discharge valve for each counting element connected across saidsource, circuit means connecting the output terminals of each countingelement with the grid and cathode of its respective discharge valve,whereby the signal voltage produced by each counting element will renderits discharge valve conductive, a capacitor located between and inelectrical connection with adjacent discharge valves for rendering thesucceeding valve non-conductive upon the preceding valve becomingconductive, a commutating circuit including a normally non-conductiveelectric discharge valve for each valve of the control circuit, means inelectrical connection with the first valve of the commutating circuitand operative upon conductivity of said first valve for supplying to theinput terminals of the first counting element electric pulses to becounted and for supplying to the resetting terminals of the remainingcounting elements electric pulses for resetting purposes, and othermeans in electrical connection wtih each remaining valve of thecommutating circuit and operative upon conductivity of its valve forrespectively supplying to the input terminals of the remaining countingelements electric pulses to be counted thereby.

11. Apparatus for counting electric current pulses by means of electriccounting elements as defined by claim 10, additionally includingconductors respectively connecting the cathodes of certain valves of thecontrol circuit with the grid of certain valves of the commutatingcircuit, whereby the latter valves are rendered conductive upon theirconnected valve in the control circuit becoming conductive.

References Cited in the file of this patent UNITED STATES PATENTS2,250,202 Matusita July 22, 1941 2,521,774 Bliss Sept. 12, 19502,521,789 Grosdofi Sept. 12, 1950 2,547,008 Hough Apr. 3, 1951 2,740,921Hough et a1. Apr. 3, 1956

